Sealing Solutions for H2 Transportation

Gases such as hydrogen are often hauled across long distances. In addition to pipelines and ships, routes on roads and railroads are frequently used. Parker Prädifa supplies reliable sealing solutions for the required ground transportation systems.

Tailored sealing solutions contribute to safe transportation of hydrogen as a gas under high pressure or in liquid state at cryogenic temperatures.

The consulting support Parker Prädifa provides to the development of components and the design of seal grooves shortens development times and optimizes the reliability of the total system.

In threaded connections and cover seals, O-rings and other static EPDM, butyl, or TPU seals are available specifically for these uses.  

For sealing of liquid hydrogen, that is below -253 °C, specialty PTFE seals preloaded with steel springs (FlexiSeals®) or resilient metal seals (Enerings) such as C-rings are used.

Sensors ensure reliable monitoring of tanks and lines and can be sealed by means of static seals even at pressures above 700 bar.

Pipelines enable efficient transportation of gases and liquids, and therefore are important for the development of a green hydrogen distribution infrastructure. Reliable, low-permeation sealing solutions for smooth and low-emission operations of pipelines are important components at many connecting points and peripherals.

Energy supply for industrial purposes, domestic uses, and mobility is intended to benefit in large parts from green hydrogen in the coming years. The utilization of existing natural gas networks and pipelines suggests itself for supplying green hydrogen to consumers. Today, biomethane and hydrogen are already being added to natural gas in regionally varying proportions. This gas network is planned to be supplemented by the construction of special hydrogen pipelines.

Reliability and leak tightness are decisive factors for operating them. Even the smallest leaks at countless connecting points, valves, flanges, and compressors add up to huge amounts of loss.

Permeability is of crucial importance especially with regard to transporting this highly volatile gas. In addition, the impact of the gas on the materials of the components used in the systems must be investigated, and adequate service life ensured.

Specifically developed materials deliver lowest permeation rates and reliable performance in extremely cold, arctic, or hot, tropical regions of the world. In addition to suitable sealing solutions and materials, Parker Prädifa offers consulting support for the correct design of sealing areas to minimize potential leakage.

In the event of particularly long distances between the places where hydrogen is produced and those where it is needed, the high-energy cargo must be hauled in liquid form or bound in a carrier on ships. For these special forms of transportation, Parker Prädifa offers reliable sealing solutions.

The energy density of gaseous hydrogen in relation to volume is relatively low. That is why long-distance maritime hauls must be able to handle liquid hydrogen. There are several ways to achieve this. One of them is transporting hydrogen below its evaporation temperature of -253 °C. Standard elastomer seals are frozen at such temperatures, non-elastic, and therefore unusable for such applications. Recommended for cryogenic applications are resilient metal seals or specialty PTFE seals pre-loaded by metal springs (FlexiSeals®) that provide reliable static as well dynamic sealing under cryogenic conditions.

Chemical compounds produced from hydrogen, such as ammonia, can be transported as energy sources and means of storage on ships as well. For liquefication, ammonia must be cooled down only to -33 °C and can be stored and hauled in simpler tanks than molecular hydrogen.

Due to health, safety, and nitrogen emission aspects, leakage must be minimized when transporting ammonia. Consequently, this makes special demands on the sealing system not only in terms of size and reliability, but total leakage of the sealing system should be minimized as well. The best leakage rates for static sealing places can be achieved with resilient metal seals. Due to their high-grade coating/plating, they can even compensate for smaller imperfections in the sealing surfaces.

Parker Prädifa supports the design of seals and selection of materials with requisite resources and technologies, enabling the development of sustainable and safe transportation systems.